Hello again @uveuvenouve,
To enter shutdown mode, you can follow this sequence
LL_PWR_SetPowerMode(LL_PWR_MODE_SHUTDOWN;
LL_LPM_EnableDeepSleep();
LL_PWR_ClearFlag_WU(); //clear any pending wake-up flags that might inadvertently wake up the MCU immediately after entering shutdown mode
__WFI(); // In shutdown mode, the __WFE(); instruction is typically not used because most peripherals, including the event system, are powered down.
You can use either the __WFE(); or __WFI(); instruction to enter sleep mode
the note "Unchanged" in Sleep mode means that the peripheral retains its state or configuration and continues to operate as it did before entering Sleep mode so it is possible to use it.
You can find low-layer power examples here: STM32CubeC0/Projects/STM32C0116-DK/Examples_LL/PWR at main · STMicroelectronics/STM32CubeC0 · GitHub
Unfortunately, there is no ready-to-use example using ADC, you'll need to configure it, but you can always ask separate questions while doing it!
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